And the battle was in the wood of Ephraim— It is supposed that this wood, which was in Gilead, not far from Maanaim, took its name either from the victory which Gideon gained over Oreb and Zeeb, kings of the Midianites, by the assistance of the Ephraimites, Joshua 7:25 or from the great daughter of the Ephraimites here by Jephthah, Judges 12:5-6. The expression in the eighth verse, the wood devoured more people that day than the sword devoured, signifies that more perished in the wood than in the field of battle: their flight, as Josephus well expresses it, was more fatal to them than the combat.
Related Commentaries of 2 Samuel 18:6
2 Samuel 18:6
6 So the people went out into the field against Israel: and the battle was in the wood of Ephraim;